to Cut or Not to Cut my front Bumper for Ram Air

[bubbafett]

A few of you might know I'm going down the Dinan ISR3 build/re-creation. I'll post a huge build thread when I'm done. -- So looking at the ISR3 prototype ol' Steve cut the roadster for ram air, then later on he cut the two holes for cooling in front of the intercooler that sorta looks like a mustache. lol -- I really like the look of the ram air hole on the far left of the bumper, I have mine all taped off, I have the skill level to make it look right, and just like the Dinan hole/grill, but I just cant bring myself to cut my bumper yet. I usually go with my gut, and I'm sure I will with this decision as well. But just wondering what other members think. (I know the ram air hole is more of an aesthetic, and only helpful at like 60+ MPH)

Might look very close to this [photo credit Randy Forbes]

100-0007_3IMG.jpg

[BimmerBreaker]

I think you should do it, but I also think it'd look best with the bumper painted after. There appears to be paint on the inner "edge" where the cut was made on that bumper, telling me it was painted after the fact.

[jrkoupe]

u can always buy another bumper....no biggie.


Just do it.....it sounds like you want too....whats the big deal?....


it wont do much anyways at most road speeds.


and its kinda not even noticeable

[rf900rkw]

One of the challenges of a Vortech supercharger on these cars is getting enough air to the filter/intake tucked in behind the bumper. I would not label it ineffective without much more study and/or data.

[bubbafett]

Step one, check. lol

DSC09240.jpg

[s8ilver]

If you don't like it in the future, it looks like the painter's tape is a pretty good match to Estoril anyways and you can just tape over it.

- - - Updated - - -

One of the challenges of a Vortech supercharger on these cars is getting enough air to the filter/intake tucked in behind the bumper. I would not label it ineffective without much more study and/or data.

Seems as though VFE thought of this somewhat. My kit has the filter so it sits just behind the brake duct, but the materials used (assuming they came with the kit...don't know, bought it that way) are sketchy. I plan to replace the flimsy accordion ducting with some silicone tubing someday, when I find the time, which is never, so nevermind.

[Terry F.]

I like it. Hope it significantly helps, though.

[BimmerBreaker]

Looks better there than when Dinan did it I think... Dinan made it too "square" - you used a larger radius on the corners which makes it look more organic, more in line with the bumper design overall.

[bubbafett]

Looks better there than when Dinan did it I think... Dinan made it too "square" - you used a larger radius on the corners which makes it look more organic, more in line with the bumper design overall.

Thanks man, that's a pretty visually sensitive comment, Yeah I rounded the corners just a tad bit more, looks like ur good with body lines as well.

If you don't like it in the future, it looks like the painter's tape is a pretty good match to Estoril anyways and you can just tape over it. .

lol!

Something I have noticed is that the Dinan cut holes do vary in location, and size just a little.

dinanisr-3mroadster1h.jpg

Just in case anybody wants to see the Dinan prototype. As seen in the Bimmer Magazine on June 1999.

DSC09246.jpg

[Remotion]

What tool did you use for cutting?

[bubbafett]

What tool did you use for cutting?

I used a 1/2 drill bit for the corners, then a dremel tool with reinforced cut off wheel, then a dremel small stone for additional shaping, then a small jewelers file to flatten edges, then finally sand paper. -- You just need a steady hand with the dremel for cutting straight lines, the use the rest of the tools for final shaping.

[Remotion]

I used a 1/2 drill bit for the corners, then a dremel tool with reinforced cut off wheel, then a dremel small stone for additional shaping, then a small jewelers file to flatten edges, then finally sand paper. -- You just need a steady hand with the dremel for cutting straight lines, the use the rest of the tools for final shaping.

Thanks. Does the paint start to chip away or does it stay attached?

[bubbafett]

The tape helps. But yes the paint is good except on the edge. It will need to be painted to look the best. -- I'm gonna try to do that myself. If I'm not happy with it I have a body shop I trust do it. --A couple years back he painted the entire bumper for $100.

[jajou318]

I think one of Greg's car in Utah has similar cuts (or one of his previous cars)

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[jajou318]

https://www.bimmerforums.com/forum/s...iece-Roadstars

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[PbFut]

Regarding paint chips around the cut. Cut the paint, at the exact line you want the opening, with an exacto knife or razor blade. Be careful. You got one shot at this. Rough cut the opening to just inside the cut line. Finish with file or other tool of choice to the exacto cut and you will have a prefect edge. I would then use some touch-up paint on the lip and overlap the edge of the paint to protect.